It has been known to prepare adducts by reaction of maleic anhydride with water-insoluble resins and oils which contain olefinic double bonds in a preferably isolated, that is to say non-conjugated, arrangement, the acid anhydride function being retained. By reaction with hydroxy-functional products, these adducts can give half-esters, with ring opening and formation of one acid group per molecule of maleic anhydride added. These carboxy-functional half-esters can be emulsified in water after at least partial neutralisation of the acid groups; binders can be formulated with these emulsions. However, the storage stability and the drying properties of paints, impregnating agents and glazes for wood and wood materials based on these binders are unsatisfactory. For this reason, these emulsions are not used as the sole binder in combination with suitable curing agents, but must be mixed with other water-dilutable binders.
Such mixtures, however, have an inadequate storage stability. There is a need, therefore, to create products from the adducts mentioned that can be formulated by reaction with suitable reaction partners to sole binders for storage-stable and fast-drying paints and glazes. In this context, hydroxyl groups are preferred as the functional groups.